Captio AI
🦻 Accessibility + 💻 Productivity App

Serbian live captions and productivity tool for traveling

For deaf and hard of hearing people.

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Captio AI app showing live captions

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Use Cases

Every situation covered

Designed for the real moments that matter — not just quiet controlled environments.

✈️Airports and boarding

Gate changes and boarding calls at Belgrade Nikola Tesla Airport (BEG) come in Serbian and English. Captio AI captions both languages so you catch gate numbers and boarding times without missing a departure.

🚂Train stations and public transport

Serbian Railways (Srpske Železnice) trains announce stops in Serbian. At Belgrade Centar or Novi Sad station, Captio AI captions the ticket window exchange and platform PA in real time.

🏨Hotels and check-in

A hotel receptionist in Belgrade's Savamala district or in Novi Sad explaining check-in details and local tips in Serbian. Place Captio AI on the desk and follow the full conversation.

🗺️Navigating and asking for help

Asking for directions near Kalemegdan Fortress in Belgrade or navigating Novi Sad's pedestrian zone. Fast Serbian from locals — Captio AI captions their reply so you find your way without confusion.

🛃Customs and immigration

Serbian border control and customs at Nikola Tesla Airport or land crossings with Hungary and North Macedonia speak quickly in formal Serbian. Captio AI captions every question.

🎭Tours and activities

A guide at Kalemegdan Fortress, Studenica Monastery, or Đerdap National Park delivering Serbian commentary on medieval and Iron Gates history. Captio AI captions in real time.

Performance

Most accurate and fastest models

Serbian
91.9%

word accuracy

independent benchmark, 2025

< 200ms
you speak
captions

real-time captions

first word appears as you speak

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Captio AI in everyday use
Why Captio AI

Built for a world that announces everything by sound

Captions any spoken exchange in real time

Airport staff, hotel receptionists, taxi drivers, tour guides. Hold the phone toward whoever is speaking and read the captions — in any setting, in any country.

60+ languages — no language barrier

Live Translator captions and translates in real time. They speak their language — you read in yours. For every country, every language, no manual setup between interactions.

Works anywhere with a data connection

Wi-Fi or mobile data. A local SIM or roaming plan keeps Captio AI running in any country — airports, hotels, rural areas, and everywhere in between.

Handles travel environments

Noisy airports, busy stations, echoing hotel lobbies. Captio AI is built for real environments — not quiet controlled rooms. It captions through the ambient noise of travel.

Discreet in any public setting

Hold the phone or place it near the speaker. Captio AI runs quietly and draws no attention — useful in customs, immigration, and any formal travel interaction where discretion matters.

Private by default

Travel conversations — customs declarations, hotel bookings, personal exchanges — are never stored or shared. Audio is processed in real time and discarded immediately.

Serbian

Why Serbian is hard to understand

Four pitch accents

  • Serbian's short/long × rising/falling tone system is carried entirely by pitch — invisible on the lips
  • Serbian has four contrastive pitch accents: short rising, short falling, long rising, long falling. These distinctions are carried by pitch contour and vowel duration — not by any change in lip or jaw position. At Belgrade Nikola Tesla Airport or a hotel desk in Novi Sad, a Serbian agent uses all four accent types to distinguish words that look identical on their face. A deaf traveler watching the speaker's lips receives no phonological information about which of the four accent types just appeared.

Ekavian vs Ijekavian

  • Belgrade Serbian and Bosnian/Montenegrin Serbian have different vowel sequences
  • Standard Serbian uses Ekavian pronunciation: historical /ě/ becomes /e/ in all positions. Ijekavian Serbian — used in Bosnia, Montenegro, and some Croatian regions — uses 'ije' or 'je' in the same positions. A deaf traveler calibrated to Belgrade Ekavian encounters Ijekavian at a hotel desk in Sarajevo or Podgorica and finds systematically different vowel sequences in many common words — without any visual warning.

Affricate minimal pairs

  • Serbian's four affricate phonemes look nearly identical on the lips
  • Serbian distinguishes two palatal affricates /tɕ/ (ć) and /tʃ/ (č), and two voiced ones /dʑ/ (đ) and /dʒ/ (dž). All four produce similar lip rounding — the distinction is made at the palate or alveolar ridge. At a Belgrade Central train station counter or the customs desk at Nikola Tesla Airport, these four sounds appear in common vocabulary and look nearly the same on a speaker's face.

Consonant clusters

  • Serbian permits complex initial clusters that arrive as rapid undifferentiated motion
  • Serbian allows complex initial consonant clusters: 'strč', 'stvar', 'tvrđava'. At a ticket window at Belgrade Centar or a bus terminal in Niš, these clusters arrive as rapid sequences of consonant movements that blur into indistinct motion for a deaf traveler reading lips, with no visual pause or anchor point between consonants.

Serbian-English code-switching in tourism

  • Belgrade hotel and tourism staff switch between Serbian and English mid-sentence
  • In Belgrade, Novi Sad, and along the Serbian tourism circuit, hotel staff and guides switch between Serbian and English mid-sentence. A deaf traveler reading Serbian lips at a Belgrade hotel or a Đerdap National Park tour desk encounters English phonology arriving without transition — requiring a sudden shift in phoneme mapping that lip-reading cannot prepare for.

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The Challenge

Hearing loss and travel accessibility in Serbia

Serbia falls within the Eastern European region, where WHO data indicates hearing loss prevalence approximately 1.35 times higher than Western Europe. The GBD 2019 study estimated 1.57 billion people globally had hearing loss — 20.3% of the world population — with Eastern Europe carrying a disproportionate burden relative to income levels. Against Serbia's population of approximately 6.8 million, regional burden estimates suggest several hundred thousand Serbians living with hearing impairment. Serbia has a documented deaf community with active organizations, and the Serbian Association of the Deaf and Hard of Hearing has representation across multiple municipalities — indicating a substantial community navigating daily communication barriers.

Serbia's travel infrastructure — including Belgrade Nikola Tesla Airport (handling over 5 million passengers annually), Serbian Railways' intercity network, and the Belgrade Metro under construction — communicates critical travel information through spoken Serbian PA. Real-time captioning is not a standard feature at Serbian airports or train stations. Serbia's tourist circuit — the medieval monasteries of Studenica, Sopoćani, and Mileševa, the Đerdap National Park on the Danube, Novi Sad's Petrovaradin Fortress, and Belgrade's Kalemegdan — attract growing international visitors; all guided tours are conducted verbally without captioning infrastructure.

Captio AI captions Serbian in real time — whether a platform announcement at Belgrade Centar, an immigration officer at Nikola Tesla Airport, or a guide at Studenica Monastery — so a deaf traveler in Serbia follows every instruction and question without depending on audio infrastructure built without them in mind.

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Privacy

What you hear stays with you.

Gone the moment it ends

Captio AI processes your audio in real time and discards it immediately. Nothing is recorded. Nothing is kept.

Not a product

Your conversations are not something Captio AI sells, shares, or monetizes — to anyone, for any reason.

Not used to train anything

What you say in a doctor's appointment or a job interview never ends up in a training dataset. Not ours. Not anyone else's.

100% PRIVATE

Private by default

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Reviews

People love Captio AI

"Platform announcements at Belgrade Centar come in fast Serbian over a PA with terrible echo. I held Captio AI near the speaker and the platform number appeared on screen. I stopped running to the board."

Marko J. 🇷🇸
marko.j***@gmail.com
Hard of hearing, Belgrade — frequent rail traveler

"The hotel receptionist in Novi Sad spoke Serbian with the Vojvodina accent — slightly different prosody from Belgrade. Captio AI handled it. Check-in details appeared on screen word by word without any issue."

Ana V. 🇷🇸
ana.v***@gmail.com
Deaf, Novi Sad — domestic traveler

"Immigration at Nikola Tesla Airport speaks fast formal Serbian. I had Captio AI open and every question appeared on screen accurately. I answered the first time without confusion or notes."

Stefan M. 🇷🇸
stefan.m***@gmail.com
Severely deaf, Belgrade — business traveler at BEG

"The guide at Đerdap National Park spoke Serbian at full speed. Captio AI captioned the full history of the Iron Gates — the Roman Trajan's Bridge, the Lepenski Vir settlement, the hydroelectric dam. Every detail."

Jelena P. 🇷🇸
jelena.p***@gmail.com
Hard of hearing, Novi Sad — tourist in Đerdap

"Platform announcements at Belgrade Centar come in fast Serbian over a PA with terrible echo. I held Captio AI near the speaker and the platform number appeared on screen. I stopped running to the board."

Marko J. 🇷🇸
marko.j***@gmail.com
Hard of hearing, Belgrade — frequent rail traveler

"The hotel receptionist in Novi Sad spoke Serbian with the Vojvodina accent — slightly different prosody from Belgrade. Captio AI handled it. Check-in details appeared on screen word by word without any issue."

Ana V. 🇷🇸
ana.v***@gmail.com
Deaf, Novi Sad — domestic traveler

"Immigration at Nikola Tesla Airport speaks fast formal Serbian. I had Captio AI open and every question appeared on screen accurately. I answered the first time without confusion or notes."

Stefan M. 🇷🇸
stefan.m***@gmail.com
Severely deaf, Belgrade — business traveler at BEG

"The guide at Đerdap National Park spoke Serbian at full speed. Captio AI captioned the full history of the Iron Gates — the Roman Trajan's Bridge, the Lepenski Vir settlement, the hydroelectric dam. Every detail."

Jelena P. 🇷🇸
jelena.p***@gmail.com
Hard of hearing, Novi Sad — tourist in Đerdap

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FAQ

Frequently asked questions

Navigate confidently in Serbian.

Captio AI is free to start

Download for free

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